CF 3 CH(ONO)CF 3 : Synthesis, IR spectrum, and use as OH radical source for kinetic and mechanistic studies

The synthesis, IR spectrum, and first‐principles characterization of CF 3 CH(ONO)CF 3 as well as its use as an OH radical source in kinetic and mechanistic studies are reported. CF 3 CH(ONO)CF 3 exists in two conformers corresponding to rotation about the RCONO bond. The more prevalent trans conformer accounts for the prominent IR absorption features at frequencies (cm −1 ) of 1766 (NO stretch), 1302, 1210, and 1119 (CF stretches), and 761 (ONO bend); the cis conformer contributes a number of distinct weaker features. CF 3 CH(ONO)CF 3 was readily photolyzed using fluorescent blacklamps to generate CF 3 C(O)CF 3 and, by implication, OH radicals in 100% yield. CF 3 CH(ONO)CF 3 photolysis is a convenient source of OH radicals in the studies of the yields of CO, CO 2 , HCHO, and HC(O)OH products which can be difficult to measure using more conventional OH radical sources (e.g., CH 3 ONO photolysis). CF 3 CH(ONO)CF 3 photolysis was used to measure k (OH + C 2 H 4 )/ k (OH + C 3 H 6 ) = 0.29 ± 0.01 and to establish upper limits of 16 and 6% for the molar yields of CO and HC(O)OH from the reaction of OH radicals with benzene in 700 Torr of air at 296 K. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 159–165, 2003